A 35-year-old man who attacked a woman police officer with an axe, leaving her with a fractured skull and a finger hanging off, has been cleared of attempted murder.

But after deliberating for two-and-a-half hours, a jury at Sheffield Crown Court found Nathan Sumner guilty of an alternative charge of causing Pc Lisa Bates grievous bodily harm with intent.

The jury had heard how Pc Bates was attacked by Sumner after she and a colleague were called to a disturbance at his Sheffield flat on April 13.

The defendant was suffering from a psychotic episode at the time, the jury of six men and six women was told.

Judge Julian Goose QC said he wanted to hear more about Sumner's current mental state before he is sentenced on December 2.

Sumner did not deny attacking Pc Bates, who was also left with an 8cm gash on the back of her head and a broken leg following the incident.

But Sumner's lawyers told Sheffield Crown Court he did not intend to kill the officer, nor cause her really serious harm.

The jury heard how Pc Bates and her colleague Pc Mark Garrett were on duty in a marked police vehicle when they were called to Sumner's maisonette in the Gleadless area of Sheffield by a neighbour.

Pc Bates told the court that Sumner shouted "aggressively" as he answered the door and attacked her colleague, punching him and pinning him against a wall.

She said she tried to pull him away but he was too strong so she used an incapacitating gas spray, which had no effect on the defendant but affected her colleague's vision.

Pc Bates told the jury that Sumner reappeared with the axe shouting "Come on then, you f*****s" and she ran, breaking her leg as she jumped down a flight of stairs in an attempt to escape.

She said Sumner then attacked her. The officer told the jury: "He was hitting me from behind. I felt it was heavy and cold and I turned around with my hands up and he just kept hitting me with the axe."

She continued: "I asked him to stop. I begged him to stop. When I was getting tired and couldn't defend myself any more, I just said 'please stop, I'm begging you'."

Pc Bates described how the attack stopped and a man who lived in another maisonette, Simon Ellis, dragged her into his home.

The jury was shown video footage of Sumner's arrest in a nearby Co-op store which shows police trying to subdue the defendant in the shop and then using a Taser on him.

David Brookes, defending, said it was agreed that his client was suffering from a psychotic episode at the time.

The defendant did not give evidence during the trial at Sheffield Crown Court.

Following the verdicts, Judge Goose said that as well as updated psychiatric reports on Sumner he also wanted an up-to-date personal impact statement from Pc Bates, detailing the effects of her ordeal and how she is recovering.

South Yorkshire Police said Pc Bates, 32, who was based at Woodseats Police Station in Sheffield, is still recovering from her injuries and remains unable to return to work.

A spokesman said the force is hopeful she will make a full recovery but this will take some time due to the severity of her injuries.

In a statement, Pc Bates said: "I would like to say thank you to the investigation team, my police colleagues and the public for their constant support and kind messages during what has been a very difficult time.

"I would also like to make special mention of the surgical assessment unit at Northern General Hospital, who provided such outstanding care. They went above and beyond in their duty to care for me and my family and it meant so much."

Detective Inspector Paul Wilson, who led the inquiry, said: "Pc Bates was responding to a routine call when she was violently attacked by Sumner back in April - she and her colleague had attended to help a potentially vulnerable member of the public. The devastating injuries inflicted upon her could have been fatal.

"He showed absolutely no regard for the consequences of his violent actions, and it's a stark reminder of the potential danger our officers face every single day, and I wish Pc Bates the very best in her continued recovery.

"Sumner not only violently attacked a police officer, but he went on to threaten staff at a local store, smashing bottles around and screaming at them. They undoubtedly must have thought they were in great danger and his behaviour would have caused serious distress.

"They, along with the member of public who so bravely helped the injured Pc, showed great courage in the face of a very dangerous and upsetting situation and I commend them all for their actions. "

Chief Inspector Lydia Lynskey said: "I have remained in regular contact with Lisa and have monitored her recovery. Unfortunately, this journey has been quite bumpy and the end isn't quite in sight as her leg is likely to need further surgery in the coming months.

"Despite the complications and setbacks, Lisa has remained positive and still manages to smile, which is testament to her. I know she has been overwhelmed by the level of support she has received, not only from her work colleagues and friends but also from the local community and public, for which she and I are truly grateful."